通过分析中高温大曲不同部位及其发酵过程中的生化指标,研究曲块部位间的差异性及其变化规律。结果表明,曲心酯化力最高,曲皮微生物数量与其他酶活最高,火圈水分与酸度最大,其他性能居中;主发酵期,发酵力速升,曲心糖化力速降、酸度快速增加,曲皮水分快速散失;潮火期,发酵力速降,酯化力和酸性蛋白酶活力上升,酸度平缓,曲皮水分进一步降低;大火期,酶活和微生物数量都低,曲心的水分和酸度开始降低;落火后,酯化力、酸性蛋白酶活力和曲心糖化力有所回升;养曲期,糖化力继续上升,酯化力与酸性蛋白酶活力缓降,曲心水分进一步降低。

The differences and variation rules between parts of Daqu with medium and high temperature were studied by analyzing the biochemical indexes and fermentation process.The results showed that the esterification ability was the highest at the centre of Daqu,the microbial number and other enzymes were the highest on the surface of Daqu; the moisture and acidity were the highest in the medial position of Daqu,and other properties lied mediacy. During the main fermentation period, the fermentation power increased rapidly; the saccharifying power droped rapidly at the centre of Daqu;but the moisture decreased quickly on the surface of Daqu. During the tidal-fire period, the fermentation power droped rapidly;the esterification ability and acidic protease activity increased; the acidity was gentle; but the moisture continues to decrease on the surface of Daqu. During the fire period,the enzyme activity and microbial numbers were both low; the water and acidity began to decrease at the centre of Daqu. After the fire period, the esterification ability and activity of acid protease rose again, so did the glycosylation ability at the centre of Daqu. During the curing period, the saccharifying power continued to rise, the esterification ability and activity of acid protease were slowly decreasing, the moisture was further reduced at the centre of Daqu.